Underground pipe pulling process and pipe pull head

Abstract

A pipe pulling technique where an adaptor is attached to the end of the pipe prior to the pipe being pulled underground, for example through a drilled hole. Attaching the adaptor to the pipe end prior to the pipe being pulled underground is faster and reduces danger to workers compared to the conventional process of attaching the adaptor to the end of the pipe after the pipe has been pulled underground.

The invention claimed is: 
     
       1. A method of pulling a pipe underground beneath an obstacle from a first side to a second side of the obstacle, comprising:
 at the first side, attaching an adaptor to an end of the pipe, the adaptor being configured to connect to a pipeline component at the second side; 
 at the first side, attaching a pull head to the adaptor; 
 pulling the pipe underground from the first side to the second side by applying a pulling force to the pull head from the second side; 
 at the second side, removing the pull head; 
 at the second side, connecting the pipeline component to the adaptor; and 
 wherein the adaptor is a pipe adaptor and the pipeline component is a second pipe. 
 
     
     
       2. A method of pulling a plastic pipe underground beneath an obstacle from a first side to a second side of the obstacle, comprising:
 at the first side, fusing a first end of a plastic pipe adaptor to an end of the plastic pipe, a second end of the plastic pipe adaptor being configured to connect to an end of a second plastic pipe; 
 at the first side, attaching a pull head to the plastic pipe adaptor after the plastic pipe adaptor is fused to the end of the plastic pipe; 
 thereafter pulling the pipe underground from the first side to the second side by applying a pulling force to the pull head from the second side; 
 at the second side, removing the pull head; and 
 at the second side, connecting the end of the second pipe to the second end of the plastic pipe adaptor after removing the pull head. 
 
     
     
       3. The method of  claim 2 , wherein connecting the end of the second pipe to the second end of the plastic pipe adaptor comprises inserting the end of the second pipe onto the second end of the plastic pipe adaptor. 
     
     
       4. A pull head used to pull a pipe underground beneath an obstacle from a first side to a second side of the obstacle, comprising:
 a pull head collar with at least first and second shell pieces that are detachably connectable to one another, the at least first and second shell pieces are sized to surround an end of the pipe when the at least first and second shell pieces are connected together; 
 each of the at least first and second shell pieces includes an interior surface and a channel is formed on the interior surface of each of the at least first and second shell pieces, wherein when the at least first and second shell pieces are connected together the channels of the at least first and second shell pieces align with one another to form a substantially continuous circumferential channel that in use receives a flange on the pipe; and 
 a pull head cap at first ends of the at least first and second shell pieces when the at least first and second shell pieces are connected together, wherein in use the pull head cap connects to a pull line that applies a pulling force to the pull head. 
 
     
     
       5. The pull head of  claim 4 , wherein each of the at least first and second shell pieces includes a flange adjacent to the first end thereof, wherein when the at least first and second shell pieces are connected together the flanges of the at least first and second shell pieces align with one another to form a substantially continuous circumferential flange;
 the pull head cap defines a circumferential channel that receives the substantially continuous circumferential flange. 
 
     
     
       6. The pull head of  claim 5 , wherein the interior surface of each of the at least first and second shell pieces includes a friction enhancement section adjacent to second ends of the at least first and second shell pieces. 
     
     
       7. The pull head of  claim 4 , wherein the pull head cap comprises pull head cap pieces that are integrally formed with the at least first and second shell pieces.